All guides · 3 min read

How long a trip should be, and why the answer is not “as long as possible”

Adding a night does not add a fixed amount to a trip. Some nights are nearly free and some are expensive. Knowing which is which changes the plan more than picking a different city.

A trip has two kinds of cost

Some of what a trip costs is paid once, no matter how long you stay. Getting there and back is the obvious one. So are the things you do once because you came: the transfer in from the airport, the bag you checked, the first supermarket run, the one museum you would feel silly missing.

The rest is paid per night: the bed, the food, moving around, the ordinary day-to-day of being somewhere. That part scales with how long you stay, roughly and with some drift.

Almost every question about trip length comes down to the ratio between those two piles. When the fixed pile is large next to the nightly one, short trips are poor value and stretching helps. When the nightly pile dominates, every extra night is close to full price and stretching mostly costs money.

The first night is the most expensive one you buy

Divide the whole trip by the number of nights and the first night carries the entire fixed cost on its own. The second night splits it in two. By the fifth it has been spread thin. This is why a long weekend somewhere far away feels absurd on paper: you are paying the whole cost of getting there to use it for two mornings.

It is also why the cost-per-night figure people quote each other is close to meaningless without the length attached. The same trip can be expensive per night and cheap in total, or the reverse.

Where the curve flattens

Because the fixed cost is being divided by a growing number, the benefit of each extra night shrinks fast. Going from two nights to four changes the arithmetic a great deal. Going from nine to eleven barely changes it at all — by then you are paying nearly the full nightly rate for each addition and getting almost no help from spreading the fixed part.

So there is usually a stretch in the middle where a trip stops being ridiculous and has not yet started being expensive. Where it sits depends entirely on how far you are going and how costly the destination is per night, which is why nobody can hand you a number that is right for every trip.

Some things get worse with length, not better

The spreading argument only applies to the fixed pile. Several things move the other way:

• Accommodation rates are not always flat. Some places price a longer stay lower, some price it higher because the dates cross a busier stretch.
• Food discipline decays. The first two days are usually planned; the seventh is more likely to be whatever is nearby.
• A longer trip crosses more of the calendar, which means more chance of hitting a period when the destination is more expensive.
• Time off work, childcare and pet care are real costs even when they never appear in a travel budget.

Test it instead of guessing

The useful move is not to decide the length first. It is to hold the budget fixed, change the number of nights, and watch what happens to the total and to which destinations survive. Two things become visible almost immediately: the point where one more night pushes you out of the budget, and the point where one fewer night saves less than you expected and costs you a day.

That second point is the one worth finding. Cutting a night that saves very little is the most common bad trade in trip planning, and it is invisible until you look at the two totals side by side.